During the Cold War, when military security was a top priority, decision making on foreign policy in Thailand was a simple process with a state-centric character. It mainly involved a number of key state agencies, including the military high command, National Security Council, Ministry of Foreign Affairs, and government leaders. After the Cold War ended, former communist countries were welcomed into the once anti-communist regional grouping of ASEAN. The Thai state agencies appeared capable of handling the post-Cold War relationship with their former enemies fairly smoothly. Though there was a hiccup in 2003, when an angry Cambodian mob burned down the Thai embassy and business buildings in Phnom Penh after a Thai actress had allegedly said that Angkor Wat belonged to Thailand, the crisis ended quickly and a normal relationship was resumed soon after. Thai-Cambodian relations, however, spiralled downwards when a civil society movement in Thailand raised a campaign over the temple of Preah Vihear which is situated on the border between the two countries. The movement was led by the People's Alliance for Democracy (PAD), sometimes known as the Yellow Shirts. The crisis began in mid-2008, when the Cambodian government proposed to the World Heritage Committee (WHC) of the United Nation Economic Social and Cultural Organisation (UNESCO) to inscribe the ancient Brahmanic Temple of Preah Vihear on the World Heritage list, and the Thai government of Samak Sundaravej lent its support to the proposal. Several border clashes took place between Thai and Cambodian troops.

The sovereignty over the temple had first became a focal point of conflict between Thailand and Cambodia in 959 when the Cambodian government under the leadership of Prince Norodom Sihanouk demanded the Thai government withdraw its troops from the temple area. When Thailand failed to comply, Sihanouk decided to take the issue to the International Court of Justice (ICJ), which awarded the temple and the territory where it is situated to Cambodia in 1962.